Istanbul, I completely understand where you are coming from. I started out on an Eddie Bauer comfort bike from Target at 340lbs. My first ride was around the block and I was winded from riding less than a mile. I built my way up, day by day, even if the next day was only an extra one hundredth of a mile. I'll never forget teh first day I rode 10 miles! It was like climbing a mountain.
I rode through every kind of weather imaginable, just like you are. I restricted calories, and the weight just flew off. I'm now down to 175 lbs, and I can hang with most people. I'm buying a road bike here soon, and I want to get into racing. Friends who haven't seen me since I was bigger don't even recognize me, literally. I have to introduce myself.
Dude, you can do it. Just keep challenging yourself. Keep working at it. And know that for every person who stares and snickers, there are five people who wish you the absolute best of luck and who have the utmost respect for your doing what no one else seems to be able to do.... losing weight through good old fashioned motivation and hard work. Good luck!